In the formulation of modern cements, adhesives and coatings, it is frequently necessary to mix two or more components immediately before use. Often, one or more of the materials gives off toxic fumes, and hence, many of the products are specifically intended to be used only in well ventilated areas. It is sometimes impossible or impractical to do the mixing in such an area and problems consequently arise under these conditions. By way of example, in orthopedic surgery where a portion of a bone is replaced as in the replacement of the hip joint, the replacement part or prosthesis is cemented to the natural bone. As mentioned, the cement must be mixed just before use and since it is to be placed within the human body, it must be formed of sterile materials that are maintained in this condition of sterility at all times. This means that the sterile materials must be removed from their packaging and mixed together within the sterile confines of the operating room, since mixing elsewhere would destroy their sterility.
Since one of the components of the commonly used cement is a volatile liquid that is quite toxic, it is important that the fumes from the liquid be removed from the operating room. In the past, this has sometimes been done by performing the mixing in a fume hood that must be built into the operating room and provided with a discharge vent that opens into the outer atmosphere. Such a solution is obviously an expensive and generally impractical one.
These problems are overcome by the present invention which provides a mixing bowl and a holder therefor in which the fumes from the mixing bowl, together with a certain amount of air are drawn off and passed through a filter that absorbs the fumes, and the cleaned air is then returned to the operating room still in sterile condition. A self-contained pump and power supply is provided to exhaust the fumes and the entire apparatus can be sterilized as needed and the sterility maintained with minimum effort.